/******************************************************************************
 * Spine Runtimes Software License
 * Version 2.3
 * 
 * Copyright (c) 2013-2015, Esoteric Software
 * All rights reserved.
 * 
 * You are granted a perpetual, non-exclusive, non-sublicensable and
 * non-transferable license to use, install, execute and perform the Spine
 * Runtimes Software (the "Software") and derivative works solely for personal
 * or internal use. Without the written permission of Esoteric Software (see
 * Section 2 of the Spine Software License Agreement), you may not (a) modify,
 * translate, adapt or otherwise create derivative works, improvements of the
 * Software or develop new applications using the Software or (b) remove,
 * delete, alter or obscure any trademarks or any copyright, trademark, patent
 * or other intellectual property or proprietary rights notices on or in the
 * Software, including any copy thereof. Redistributions in binary or source
 * form must include this license and terms.
 * 
 * THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

using UnityEngine;
using System.Collections;

public class SkeletonUtilityEyeConstraint : SkeletonUtilityConstraint {

	public Transform[] eyes;
	public float radius = 0.5f;
	public Transform target;
	public Vector3 targetPosition;
	public float speed = 10;
	Vector3[] origins;
	Vector3 centerPoint;

	protected override void OnEnable () {
		if (!Application.isPlaying)
			return;

		base.OnEnable();

		Bounds centerBounds = new Bounds(eyes[0].localPosition, Vector3.zero);
		origins = new Vector3[eyes.Length];
		for (int i = 0; i < eyes.Length; i++) {
			origins[i] = eyes[i].localPosition;
			centerBounds.Encapsulate(origins[i]);
		}

		centerPoint = centerBounds.center;
	}

	protected override void OnDisable () {
		if (!Application.isPlaying)
			return;

		base.OnDisable();
	}

	public override void DoUpdate () {

		if (target != null)
			targetPosition = target.position;

		Vector3 goal = targetPosition;

		Vector3 center = transform.TransformPoint(centerPoint);
		Vector3 dir = goal - center;

		if (dir.magnitude > 1)
			dir.Normalize();

		for (int i = 0; i < eyes.Length; i++) {
			center = transform.TransformPoint(origins[i]);
			eyes[i].position = Vector3.MoveTowards(eyes[i].position, center + (dir * radius), speed * Time.deltaTime);
		}

	}
}
